Thanks for taking the time to report this bug and helping to make Ubuntu better. Since the package referred to in this bug is in universe or multiverse, it is community maintained. If you are able, I suggest coordinating with upstream and posting a debdiff for this issue. When a debdiff is available, members of the security team will review it and publish the package. See the following link for more information: https://wiki.ubuntu.com/SecurityTeam/UpdateProcedures

That revision really fixes it in a more general way: without "=", spaces or newlines, you can't do much harm. Sure, you can write arbitrary values in the config file, but still nothing that would get executed.